Substitution Consequences on Electric and Magnetic Behaviour of Nanoferrites

<p>Modification of the magnetic properties in a solid-state material upon external stimulus has attracted much attention in the recent years for their potential applications as switches and sensors. Within the field of coordination polymers, gas sorption studies typically focus on porous solids, with the gas molecules accommodating in the channels. Here we present a 1D non-porous coordination polymer capable of incorporating HCl gas molecules, which not only causes a reordering of its atoms in the solid state but also provokes dramatic changes in the magnetic behaviour. Subsequently, a further solid-gas transformation can occur with the extrusion of HCl gas molecules causing a second structural rearrangement which is also accompanied by modification in the magnetic path between the metal centres. Unequivocal evidence of the two-step magnetostructural transformation is provided by X-ray single-crystal diffraction.</p>

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Anomalous magnetic behaviour at nano-scale of Mn2+-substituted magnesio-ferrite synthesized by auto-combustion technique

Indian Journal of Physics ◽

10.1007/s12648-021-02169-z ◽

2021 ◽

Author(s):

Laxmi J. Hathiya ◽

J. D. Baraliya ◽

Avik Das ◽

Debasis Sen ◽

A. M. Gismelseed ◽

...

Keyword(s):

Magnetic Behaviour ◽

Nano Scale ◽

Auto Combustion ◽

Combustion Technique

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Solvent-Induced Hysteresis Loop in Anionic Spin Crossover (SCO) Isomorph Complexes

Magnetochemistry ◽

10.3390/magnetochemistry7060075 ◽

2021 ◽

Vol 7 (6) ◽

pp. 75

Author(s):

Emmelyne Cuza ◽

Samia Benmansour ◽

Nathalie Cosquer ◽

Françoise Conan ◽

Carlos J. Gómez-García ◽

...

Keyword(s):

Metal Ion ◽

Spin Crossover ◽

Magnetic Behaviour ◽

Magnetic Studies ◽

Tridentate Ligands ◽

Tripodal Ligand ◽

Single Crystal Structures ◽

One Step ◽

Lower Temperature ◽

Step Transition

Reaction of Fe(II) with the tris-(pyridin-2-yl)ethoxymethane (py3C-OEt) tripodal ligand in the presence of the pseudohalide ancillary NCSe- (E = S, Se, BH3) ligand leads to the mononuclear complex [Fe(py3C-OEt)2][Fe(py3C-OEt)(NCSe)3]2·2CH3CN (3), which has been characterised as an isomorph of the two previously reported complexes, Fe(py3C-OEt)2][Fe(py3C-OEt)(NCE)3]2·2CH3CN, with E = S (1), BH3 (2). X-ray powder diffraction of the three complexes (1–3), associated with the previously reported single crystal structures of 1–2, revealed a monomeric isomorph structure for 3, formed by the spin crossover (SCO) anionic [Fe(py3C-OEt)(NCSe)3]− complex, associated with the low spin (LS) [Fe(py3C-OEt)2]2+ cationic complex and two solvent acetonitrile molecules. In the [Fe(py3C-OEt)2]2+ complex, the metal ion environment involves two py3C-OEt tridentate ligands, while the [Fe(py3C-OEt)(NCSe)3]− anion displays a hexacoordinated environment involving three N-donor atoms of one py3C-OEt ligand and three nitrogen atoms arising from the three (NCSe)− coligands. The magnetic studies for 3 performed in the temperature range 300-5-400 K, indicated the presence of a two-step SCO transition centred around 170 and 298 K, while when the sample was heated at 400 K until its complete desolvation, the magnetic behaviour of the high temperature transition (T1/2 = 298 K) shifted to a lower temperature until the two-step behaviour merged with a gradual one-step transition at ca. 216 K.

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Effect of coverage on the magnetic properties of -COOH, -SH, and -NH2 ligand-protected cobalt nanoparticles

Nanoscale ◽

10.1039/d1nr01081f ◽

2021 ◽

Author(s):

Barbara Farkas ◽

Nora Henriette De Leeuw

Keyword(s):

Magnetic Properties ◽

Magnetic Nanoparticles ◽

Cobalt Nanoparticles ◽

Magnetic Behaviour

Implementation of magnetic nanoparticles in biomedicine requires their passivation, which often comes at a cost of diminished magnetic properties. For the design of nano-agents with targeted magnetic behaviour, it is...

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Influence of Magnetoelastic Anisotropy on Properties of Nanostructured Microwires

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.646.59 ◽

2013 ◽

Vol 646 ◽

pp. 59-66 ◽

Cited By ~ 1

Author(s):

Arcady Zhukov ◽

Margarita Churyukanova ◽

Lorena Gonzalez-Legarreta ◽

Ahmed Talaat ◽

Valentina Zhukova ◽

...

Keyword(s):

Heat Capacity ◽

Hysteresis Loops ◽

Magnetic Behaviour ◽

Soft Magnetic ◽

Magnetoelastic Anisotropy ◽

Thermal Expansion Coefficients ◽

Magnetoelastic Energy ◽

Expansion Coefficients ◽

The Difference ◽

Magneto Resistance

We studied the effect ofthe magnetoelastic ansitropy on properties of nanostructured glass-coated microwires with soft magnetic behaviour (Finemet-type microwires of Fe70.8Cu1Nb3.1Si14.5B10.6, Fe71.8Cu1Nb3.1Si15B9.1 and Fe73.8Cu1Nb3.1Si13B9.1 compositions) and with granular structure (Cu based Co-Cu microwires). The magnetoelastic energy originated from the difference in thermal expansion coefficients of the glass and metallic alloy during the microwires fabrication, affected the hysteresis loops, coercivity and heat capacity of Finemet-type microwires. Hysteresis loops of all as-prepared microwires showed rectangular shape, typical for Fe-rich microwires. As expected, coercivity, HC, of as-prepared microwires increases with decreasing of the ratio ρ defined as the ratio between the metallic nucleus diameter, d to total microwire diameter, D. On the other hand we observed change of heat capacity in microwires with different ratio ρ. In the case of Co-Cu microwires ρ- ratio affected the structure and the giant magneto-resistance of obtained microwires.

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Synthesis and Magnetic Behaviour of p-O2NC6F4CNSSN

Phosphorus Sulfur and Silicon and the Related Elements ◽

10.1080/10426500108546608 ◽

2001 ◽

Vol 169 (1) ◽

pp. 133-136 ◽

Cited By ~ 1

Author(s):

Christopher M. Pask ◽

Robert J. Less ◽

Jeremy M. Rawson ◽

Fernando Palacio ◽

Patricia Oliete

Keyword(s):

Magnetic Behaviour

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Magnetic behaviour of vanadium +II in one- and two-dimensional systems

Physica B+C ◽

10.1016/0378-4363(77)90653-2 ◽

1977 ◽

Vol 86-88 ◽

pp. 702-704 ◽

Cited By ~ 28

Author(s):

M. Niel ◽

C. Cros ◽

G. Le Flem ◽

M. Pouchard ◽

P. Hagenmuller

Keyword(s):

Magnetic Behaviour ◽

Two Dimensional

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Structural chemistry and magnetic behaviour of the ternary silicides UCuxSi2−x (0.28≤x≤0.96)

Journal of Alloys and Compounds ◽

10.1016/s0925-8388(98)00817-2 ◽

1999 ◽

Vol 282 (1-2) ◽

pp. 44-51 ◽

Cited By ~ 6

Author(s):

S. Pechev ◽

B. Chevalier ◽

B. Darriet ◽

J. Etourneau

Keyword(s):

Magnetic Behaviour ◽

Structural Chemistry

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Synthesis and Characterization of Some Novel Homo- and Hetero-Diradicals of Hydrazyl and Nitroxide Type

Australian Journal of Chemistry ◽

10.1071/ch06469 ◽

2007 ◽

Vol 60 (3) ◽

pp. 173 ◽

Cited By ~ 4

Author(s):

Petre Ionita ◽

Floriana Tuna ◽

Marius Andruh ◽

Titus Constantinescu ◽

Alexandru T. Balaban

Keyword(s):

Free Radical ◽

Potassium Permanganate ◽

Lead Dioxide ◽

Magnetic Behaviour ◽

Synthesis And Characterization ◽

Stable Free Radical ◽

Ms Analysis ◽

New Compounds

Starting from the well known stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH; 2a) and its congener 2,2-diphenyl-1-(4-cyano-2,6-dinitrophenyl)hydrazyl 2b, or from their reduced hydrazine counterparts 1a,b, it was possible to obtain the p-quinonoid compounds 4a,b by oxidation with ceric (Ce4+) sulfate, which by reduction gave the corresponding hydroxyl derivatives 2-phenyl-2-(4-hydroxyphenyl)-1-picrylhydrazine 5a or 2-phenyl-2-(4-hydroxyphenyl)-1-(4-cyano-2,6-dinitrophenyl)hydrazine 5b. These hydroxyl derivatives (5a,b) react with 4-carboxy-TEMPO or 2,2-diphenyl-1-(4-carboxy-2,6-dinitrophenyl)hydrazine to form the corresponding esters 6a,b or 8a,b. These esters (6a,b and 8a,b) lead to the hybrid hetero diradicals (nitroxide–hydrazyl type) 7a,b or homo biradicals (hydrazyl–hydrazyl type) 9a,b by oxidation with lead dioxide or potassium permanganate. The new compounds were characterized by UV-vis, NMR, EPR, and MS analysis, and their magnetic behaviour was investigated.

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